[This document was taken from the Senate Document noted below rather
than from the PHA. Some page numbers may be different between the two
copies. The page numbers in [brackets] are from the original and will
be the same in both copies. LWJ]
77TH Congress SENATE DOCUMENT
2d Session No. 159
SENATE

ATTACK UPON PEARL HARBOR
BY JAPANESE ARMED FORCES

REPORT OF THE COMMISSION APPOINTED BY THE PRESIDENT OF THE UNITED STATES TO INVESTIGATE AND REPORT THE FACTS RELATING TO THE ATTACK MADE BY JAPANESE ARMED FORCES UPON PEARL HARBOR IN THE TERRITORY OF HAWAII ON DECEMBER 7, 1941

S. Docs., 77-2, VOL. 8 - 8
[SUBMITTED BY MR. HAYDEN]
(INDEX ADDED INTERCALARY, LWJ)
FINDING OF FACT ........................................................ 3
SUMMARY OF THE MORE IMPORTANT FACTS .................................... 17
CONCLUSIONS............................................................. 19
IN THE SENATE OF THE UNITED STATES,
January 28 (Legislative Day, January 23), 1942.
ORDERED, That the report of the Commission appointed by the President to
investigate and report the facts relating to the attack made by Japanese
armed forces upon Pearl Harbor in the Territory of Hawaii on December 7,
1941, be printed as a Senate Document.
1 JAPANESE ATTACK UPON PEARL HARBOR
JAPANESE ATTACK UPON PEARL HARBOR
JANUARY 23,1942
The PRESIDENT,
The White House
SIR: The undersigned were appointed by Executive order of December
18,1941, which defined our duties as a commission thus:
"to ascertain and report the facts relating to the attack made by
Japanese armed forces upon the Territory of Hawaii on December 7, 1941.
"The purposes of the required inquiry and report are to provide bases
for sound decisions whether any derelictions of duty or errors of
judgment on the part of United States Army or Navy personnel contributed
to such successes as were achieved by the enemy on the occasion
mentioned, and, if so, what these derelictions or errors were, and who
were responsible therefor."
The Congress speedily supplemented the Executive order by granting the
Commission power to summon witnesses and examine them under oath.
The Commission held three meetings in Washington, December 18, 19, and
20, and, on the latter day, proceeded to Honolulu, T. H., where the
Commission arrived December 22 and held meetings December 22, 23, 24,
and 26 at the headquarters of the Hawaiian Department, Fort Shafter, and
December 27, 29, 30, and 31, 1941, and January 2 and 3, 1942, at the
submarine base, Pearl Harbor; and January 5, 6, 7, 8, and 9 at the Royal
Hawaiian Hotel, Honolulu. January 10 the commission left Honolulu for
Washington, D. C.; held meetings January 12, 13, and 14; arrived at
Washington January 15 and held further meetings January 16, 17, 18, 19,
20, 21, 22, and 23.
The Commission examined 127 witnesses and received a large number of
documents. All members of the Military and Naval Establishments, and
civil officers and citizens who were thought to have knowledge of facts
pertinent to the inquiry, were summoned and examined under oath. All
persons in the island of Oahu, who believed they had knowledge of such
facts, were publicly requested to appear, and a number responded to the
invitation and gave evidence.
Various rumors and hearsay statements have been communicated to the
Commission. The Commission has sought to find and examine witnesses who
might be expected to have knowledge respecting them. We believe that our
findings of fact sufficiently dispose of most of them.
The evidence touches subjects which in the national interest should
remain secret. We have, therefore, refrained from quotation of testimony
or documentary proof. Our findings, however, have been made with the
purpose fully and accurately to reflect the testimony, which as respects
matters of fact is substantially without contradiction.
2 JAPANESE ATTACK UPON PEARL HARBOR
It is true, as we have found, that due to the enormous demand on the
Nation's capacity to produce munitions and war supplies, there was a
deficiency in the provision of materiel for the Hawaiian area. This was
but natural, in the circumstances, and was well known to the Government
departments and local commanders. We have made no detailed findings on
the subject since, as will appear from our report, we find that this
deficiency did not affect the critical fact of failure to take
appropriate measures with the means available.
At our hearings reference was made to what has long been a matter of
common knowledge that there are, and have been, diverse views of
national policy respecting the basing of the entire United States
Pacific Fleet at Pearl Harbor, T. H. We feel that the national policy
in this matter is one that has been settled by those responsible for
such decisions and that it is not within our province that of finding
the facts respecting the attack of December 7, and the responsibility
for the resulting damage to the United States to discuss any such topic.
Regrettable loss of life and extensive damage resulted from the air
raid. The nature of that damage and the details of the measures taken to
repair it have no direct bearing on the execution of the mandate
appointing this Commission, and the subject is dealt with in our report
only to the extent that it bears on questions of responsibility for the
disaster.
The evidence taken covered a wide scope. The Commission intentionally
invited such latitude of testimony and inquiry in the belief that
thereby incidental light might be thrown upon the main issues involved.
As an example, the Commission heard evidence to show what had been done
at Pearl Harbor and on the island of Oahu by naval and military commands
subsequent to December 7, 1941, in the view that this might throw some
light upon the matters submitted for our consideration. Again, the
Commission heard much testimony as to the population of Hawaii, its
composition, and the attitude and disposition of the persons composing
it, in the belief that the facts disclosed might aid in appraising the
results of investigative, counterespionage, and anti-sabotage work done
antecedent to the attack of December 7, 1941.
The Commission visited the naval base at Pearl Harbor and air fields of
the Military and Naval Establishments, as well as the Army posts and
forts and certain of the coast fortifications on the island of Oahu.
The minutes of each meeting of the Commission are of record. The
statements of witnesses received in the meetings previous to that of
December 22 have been recorded in summaries. All testimony received at
the meeting of December 22 and the subsequent meetings was
stenographically reported and transcribed.
The oral evidence received amounts to 1,887 typewritten pages, and the
records and documents examined exceed 3,000 printed pages in number.
Appended hereto is a map of the island of Oahu showing the location of
the principal naval and military establishments.
All the testimony and evidence received have been considered and, as the
result of its deliberations, the Commission submits the following:
JAPANESE ATTACK UPON PEARL HARBOR 3
FINDING OF FACT
I
About 7:65 a. m. Honolulu time (1: 25 p. m. Eastern standard time) on
Sunday, December 7, 1941, Japanese forces attacked Army and Navy
installations and ships of the Pacific Fleet in Oahu, T. H .
Although the United States and Japan were at peace on that morning,
Japan planned to announce to the Secretary of State of the United States
at 1 p. m. of that day, eastern standard time (7:30 a. m. Honolulu time)
the severance of diplomatic relations and simultaneously to attack the
island of Oahu and Pearl Harbor. The military preparations for this
breach of international faith and honor were put in train and the forces
for its consummation had been dispatched weeks prior to any intimation
of the planned severance of relations.
II
The Territory of Hawaii comprises the group of islands known as the
Hawaiian Islands. This group consists of the larger islands Hawaii,
Maui, Molokai, Oahu, and Kauai and a number of smaller islands. They
extend from Hawaii in the south some 300 miles in a northwesterly
direction, including Kauai in the north. For purposes of certain
developments and protection, the islands of Midway, Wake, Johnston,
Palmyra, Christmas, and Canton had been placed under the responsible
naval and military heads in the Hawaiian area.
The importance of the Territory of Hawaii from a national defense
standpoint is the fact that Pearl Harbor, the main outlying naval base
in the Pacific, is located in the island of Oahu, one of the Hawaiian
group. For this reason all measures for the protection and defense of
the Territory have centered in and around Oahu, the other islands being
garrisoned by minor forces only. A main outlying naval base such as
Pearl Harbor, is intended for the use of the fleet for taking on fuel
and supplies, for recreation and rest of the fleet personnel, and for
the repair and refitting of ships.
III
It has been well known that the policy of the United States as to
affairs in the Pacific was in conflict with the policies of other
governments. It was realized by the State, War, and Navy Departments of
the United States that unless these policies were reconciled war in the
Pacific was inevitable.
IV
Plans and preparations against the contingency of war are the joint
responsibility of the military and naval authorities, and, within the
limits of funds and authorizations provided by the Congress, were being
ceaselessly carried out.
Under these plans the general function of the Army is to conduct
military operations in direct defense of United States territory. The
general function of the Navy is to conduct naval operations to gain and
maintain control of vital sea areas, thereby contributing to the defense
of the coastal frontiers.
4 JAPANESE ATTACK UPON PEARL HARBOR
Specific plans for the protection of the Hawaiian area against every
contingency had been prepared. These included joint Army and Navy war
plans, and War Department and Navy Department plans subsidiary thereto
which establish the Hawaiian coastal frontier, assign tasks and forces
to both Army and Navy for its joint defense, and prescribe that the
system of coordination between the responsible Army and Navy commanders
shall be by mutual cooperation.
V
The responsibility for the Joint defense of the Hawaiian coastal
frontier rested upon the commanding general, Hawaiian Department, and
the commandant, Fourteenth Naval District, the latter acting as a
subordinate of the commander in chief of the Pacific Fleet. The
commander in chief of the fleet, in addition, was assigned the task of
protecting the territory within the Hawaiian naval coastal frontier by
destroying hostile expeditions and by supporting land and air forces in
denying the enemy the use of land positions within that frontier, and
the further task of covering the operations of the Hawaiian coastal
frontier forces. The commanding general, Hawaiian Department, could
properly deal, respecting defense measures and dispositions, with either
the commander in chief of the Pacific Fleet or the commandant of the
Fourteenth Naval District.
The commander in chief of the Pacific Fleet from February 1 to December
17, 1941, was Admiral Husband E. Kimmel. The commandant, Fourteenth
Naval District, from April 11, 1940, to date is Rear Admiral Claude C.
Bloch. The commanding general, Hawaiian Department, from February 7 to
December 17, 1941, was Lt. Gen. Walter C. Short.
A local joint defense plan entitled "Joint Coastal Frontier Defense
Plan, Hawaiian Coastal Frontier," was prepared by General Short and Rear
Admiral Bloch, the latter acting under the direction of Admiral Kimmel.
Each commander adopted a standing operating procedure, or standing
orders, to carry out his obligation under the joint agreement. This
joint coastal frontier defense plan was intended to become operative
upon order of the War and Navy Departments or, as agreed upon by the
local commanders in the case of an emergency, a threat of hostile
action, or the occurrence of war.
The means available to the Army, for the fulfillment of its mission,
consist of coast defense and antiaircraft artillery, mobile ground
forces, the Hawaiian air force, and an aircraft warning service. The
supporting elements of the Navy consist of local naval defense forces
comprising light surface craft and shore-based aircraft not assigned to
the fleet. The fleet as such was not charged with the defense of Pearl
Harbor, except that certain aircraft attached to the fleet when present,
and the antiaircraft weapons of such units of the fleet as were in port,
were available.
It was recognized that, prior to furnishing the full war strength
garrison, insufficient forces were available to maintain all the
defenses on a war footing for extended periods of time. The responsible
commanders made numerous recommendations to the War and
JAPANESE ATTACK UPON PEARL HARBOR 5
Navy Departments for additional forces, equipment, and funds which they
deemed necessary to insure the defense of the Hawaiian coastal frontier
under any eventuality. The national situation permitted only a partial
filling of these requirements. However, presupposing timely dispositions
by the Army and Navy commands in Hawaii, the forces available to them
were adequate to frustrate a surprise air attack or greatly to mitigate
its effectiveness.
VII
In a letter of January 24, 1941, the Secretary of the Navy advised the
Secretary of War that the increased gravity of the Japanese situation
had prompted a restudy of the problem of the security of the Pacific
Fleet while in Pearl Harbor. The writer stated:
"If war eventuates with Japan, It is believed easily possible that
hostilities would be initiated by a surprise attack upon the fleet or
the naval base at Pearl Harbor."
The writer stated that the
"inherent possibilities of a major disaster "
warranted further speedy action to
"increase the joint readiness of the Army and Navy to withstand a raid
of the character mentioned * * *"
The letter proceeded:
"The dangers envisaged in their order of importance and probability are
considered to be: (1) Air bombing attack, (2) air torpedo plane attack,
(3) sabotage, (4) submarine attack, (5) mining, (6) bombardment by
gunfire."
It stated the defenses against all but the first two were then
satisfactory, described the probable character of an air attack and
urgent consideration by the Army of dispositions to discover and meet
such attack and provision of additional equipment therefor. It concluded
with recommendations for the revision of joint defense plans with
special emphasis on the coordination of Army and Navy operations against
surprise aircraft raids. It also urged the conduct of joint exercises to
train the forces to meet such raids.
The Secretary of War replied February 7, 1941, giving the present and
prospective status of the Hawaiian Department in respect of airplanes
and antiaircraft artillery, and stating with respect to the other
proposals of the Secretary of the Navy that a copy of the letter was
being forwarded to the commanding general, Hawaiian Department, with
direction to him to cooperate with the local naval authorities in making
the suggested measures effective.
Admiral Kimmel and General Short received copies of these letters at
about the time they assumed the commands which they held December 7,
1941. Rear Admiral Bloch also received copies.
The joint coastal frontier defense plan and plans subsidiary thereto
envisaged the possibility of an air attack and estimated that, if made
it would most likely occur at dawn. An agreement between the Hawaiian
air force and the commander, Navy Patrol Wing 21 established the
responsibilities for the joint use and operation of the available air
forces of the Army and Navy. The standing operating procedure, Hawaiian
Department, and standing orders of the United States Pacific Fleet and
the Fourteenth Naval District also pre-
6 JAPANESE ATTACK UPON PEARL HARBOR
scribed measures for protection against air attack. Frequent joint
drills and exercises were conducted during the year 1941 to insure such
measures would be effective.
VIII
For months prior to December 7, 1941, the Secretary of State was
repeatedly in contact with the Secretary of War and the Secretary of the
Navy, not only in Cabinet meetings, but in meetings of the war council;
and on the occasions of those contacts and in conference, with the
Secretary of War and the Secretary of the Navy, discussed negotiations
with Japan and the growing tensity of the relations of the United States
with Japan. At meetings of the war council the Chief of Staff and the
Chief of Naval Operations were also present. The Secretary of State
constantly kept the Secretary of War and the Secretary of the Navy
informed of the progress of the negotiations, and all three of these
officials were cognizant of the growing threat of hostilities and of the
military and naval needs and measures consequent thereupon. The
Secretaries of War and Navy were in constant touch with the Chief of
Staff and the Chief of Naval Operations, and imparted to them the
information received from the Secretary of State and the results of
their conferences with him. The latter officers in turn advised the
responsible commanders in the field of the progress of events and of the
growing threat of hostilities. The responsible commanders in the
Hawaiian area were aware that previous Japanese actions and demonstrated
Axis methods indicated that hostile action might be expected prior to a
declaration of war.
IX
October 16, 1941, the commanding general, Hawaiian Department, and the
commander in chief of the fleet were advised by the War and Navy
Departments of the changes in the Japanese Cabinet, of the probability
of hostilities between Japan and Russia, and of the possibility of an
attack by Japan on Great Britain and the United States. Both commanders
were warned to take precautions and to make preparatory dispositions
which would not disclose their strategic intentions or constitute
provocation as against Japan. Admiral Kimmel made certain dispositions
of units of the fleet, and placed additional security measures in effect
in the operating areas outside Pearl Harbor. At that time various task
forces of the Navy were engaged in training operations and maneuvers
which were deemed highly important to the training of the fleet
personnel, and the Army was also conducting intensive training,
particularly of its air arm. The responsible commanders testified that
to undertake increased defense measures respecting Pearl Harbor and the
Hawaiian area would necessitate curtailment of training, if not its
virtual suspension, and they thought the situation was not such as to
require this.
November 24, 1941, the Chief of Naval Operations sent a message to
Admiral Kimmel, in which he stated that in the opinion of the Navy
Department a surprise aggressive movement in any direction by the
Japanese, including an attack on the Philippines or Guam, was a
possibility; that the doubt as to favorable outcome of pending
negotiations, the statements of the Japanese Government, and the
movements of its army and naval forces, supported this opinion. The
JAPANESE ATTACK UPON PEARL HARBOR 7
communication enjoined secrecy to prevent complication of the tense
existing situation. The message advised that the Chief of Staff of the
Army requested that the local senior Army officers be advised that he
concurred in the despatch. This message was seen by both the commander
in chief of the fleet and the commanding general of the Hawaiian
Department.
The responsible commanders in Hawaii knew that negotiations had been
continued through October and November, and were awaiting further
developments. November 27, 1941, the Chief of Staff of the Army informed
the commanding general, Hawaiian Department, that the negotiations with
Japan seemed to be ended, with little likelihood of their resumption;
that Japanese action was unpredictable; that hostilities on the part of
Japan were momentarily possible; that in the event hostilities could not
be avoided the United States desired that this Nation should not commit
the first overt act; that the department commander was not to be
restricted to any course which would jeopardize his defense. The message
directed him, even prior to hostile action, to undertake such
reconnaissance and other measures as he deemed necessary, but to carry
them out in such a way as not to alarm the civil population or disclose
his intent. He was directed to restrict the information contained in the
message to the minimum of essential officers, and to report to the Chief
of Staff the measures taken. The purport of this message was
communicated by the department commander to the commander in chief of
the Pacific Fleet.
On the same day (November 27, 1941), the Chief of Military Intelligence
sent a message to the intelligence officer on the staff of the
commanding general, Hawaiian Department, directing him to inform the
commanding general and his chief of staff that negotiations with Japan
had practically ceased; that hostilities might ensue; and that
subversive activity might be expected.
On the same day (November 27, 1941), the Chief of Naval Operations sent
a message to the commander in chief of the Pacific Fleet, which stated
in substance that the dispatch was to be considered a war warning; that
the negotiations with Japan in an effort to stabilize conditions in the
Pacific had ended; that Japan was expected to make an aggressive move
within the next few days; that an amphibious expedition against either
the Philippines, Thai, or Kra Peninsula or possibly Borneo, was
indicated by the number and equipment of Japanese troops and the
organization of their naval task forces. It directed the execution of a
defensive deployment in preparation for carrying out war tasks. It
stated that Guam, Samoa, and continental districts had been directed to
take appropriate measures against sabotage, and that a similar warning
was being sent by the War Department. It ordered that the addressee
inform naval district and Army authorities. The commander in chief of
the fleet communicated the purport of this message to the general
commanding the Hawaiian Department of the Army.
At the time of our hearing General Short had no independent recollection
of the last-mentioned message, although he felt that it must have been
shown to him.
November 27, 1941, the commanding general, Hawaiian Department, in
response to the direction of the Chief of Staff that he report measures
taken, informed the Chief of Staff that he had alerted his
8 JAPANESE ATTACK UPON PEARL HARBOR
command against sabotage and that he was maintaining liaison with the
Navy. No reply referring to this message was sent by the War Department;
but General Short testified that he considered the Adjutant General's
message referred to in the next succeeding paragraph a reply.
November 28, 1941, the commanding general, Hawaiian Department, received
from The Adjutant General of the Army a message stating that the
critical situation required every precaution to be taken at once against
subversive activities, within the scope of the Army's responsibility;
that all necessary measures be taken to protect military establishments,
property, and equipment against sabotage, against propaganda affecting
Army personnel, and against all espionage. The message disclaimed
ordering any illegal measures, and warned that protective measures
should be confined to those essential to security, so as to avoid
unnecessary publicity and alarm. The message stated that identical
communications were being sent to all air stations and, on November 28,
the Chief of the Army Air Forces sent such an identical message to the
commanding general, Hawaiian Air Force.
November 29, 1941, the commanding general, Hawaiian Department, replied
to the last-mentioned message, outlining at length and in detail the
measures taken to prevent sabotage of military establishments and
property and essential industrial and public-utility installations. No
reply was sent by the War Department to this message. General Short
testified that he considered this series of messages a tacit agreement
that the measures taken were all that were intended by the Department.
November 29, 1941, the Chief of Naval Operations sent a message to the
commander in chief of the fleet, which was in substance a quotation of
the Chief of Staff's despatch of November 27 to the commanding general,
Hawaiian Department; and in addition directed the addressee to take no
offensive action until Japan had committed an overt act, and ordered
certain action in case hostilities should occur.
November 30, 1941, the Chief of Naval Operations sent a despatch to the
commander in chief of the Asiatic Fleet, and also forwarded the message
to the commander in chief of the Pacific Fleet for his information, in
which it was stated the indications were that Japan was about to launch
an attack on the Kra Isthmus, directing the commander in chief of the
Asiatic Fleet to do certain scouting, but to avoid the appearance of
attacking. Admiral Kimmel testified that he had viewed this message as
indicating that the Navy Department was not expecting a Japanese attack
on Hawaii.
The Navy Department sent three messages to the commander in chief of the
Pacific Fleet; the first of December 3, 1941, stated that it was
believed certain Japanese consulates were destroying their codes and
burning secret documents; the second of December 4, 1941, instructed the
addressee to destroy confidential documents and means of confidential
communication, retaining only such as were necessary, the latter to be
destroyed in event of emergency (this was sent to the commander in chief
of the Pacific Fleet for information only); and the third of December 6,
1941, directing that in view of the tense situation the naval commands
on the outlying Pacific islands might be authorized to destroy
confidential papers then or later, under conditions of greater
emergency, and that those essential to continued operations should be
retained until the last moment.
JAPANESE ATTACK UPON PEARL HARBOR 9
The foregoing messages did not create in the minds of the responsible
officers in the Hawaiian area apprehension as to probable imminence of
air raids. On the contrary they only served to emphasize in their minds
the danger from sabotage and surprise submarine attack. The necessity
for taking a state-of-war readiness which would have been required to
avert or meet an air-raid attack was not considered.
X
December 1,1941, the Director of Naval Intelligence issued a bulletin
which, under the caption "Japanese Naval Situation,"' stated:
"Deployment of naval forces to the southward has indicated clearly that
extensive preparations are under way for hostilities. At the same time
troop transports and freighters are pouring continually down from Japan
and northern China coast ports headed south, apparently for French
Indochina and Formosan ports. Present movements to the south appear to
be carried out by all individual units, but the organization of an
extensive task force, now definitely indicated, will probably take
sharper form in the next few days. To date this task force, under the
command of the commander in chief, Second Fleet, appears to be
subdivided into two major task groups, one gradually concentrating off
the southeast Asiatic coast, the other in the Mandates. Each constitutes
a strong striking force of heavy and light cruisers, units of the
combined air force, destroyer and submarine squadrons. Although one
division battleships also may be assigned, the major capital ship
strength remains in home waters, as well as the greatest portion of: the
carriers."
The Naval Intelligence Service in Hawaii, due to lack of information
indicating that the bulk of Japanese carriers were at sea, concluded
they were in home ports.
XI
At about noon, eastern standard time (6:30 a.m. Honolulu time), December
7, an additional warning message, indicating an almost immediate break
in relations between the United States and Japan, was its dispatched by
the Chief of Staff after conference with the Chief Naval Operations, for
the information of responsible Army and Navy commanders. Every effort
was made to have the message reach Hawaii in the briefest possible time,
but due to conditions beyond the control of anyone concerned the
delivery of this urgent message was delayed until after the attack.
XII
The commanding general, Hawaiian Department, the commander in chief of
the fleet, and the commandant, Fourteenth Naval District, their senior
subordinates, and their principal staff officers, considered the
possibility of air raids. Without exception they believed that the
chance of such a raid while the Pacific Fleet was based upon Pearl
Harbor were practically nil. The attack of Sunday, December 7, 1941, was
therefore a complete surprise to each of them.
While General Short and Admiral Kimmel conferred frequently with respect
to joint Army-Navy plans and procedures, they did not, subsequent to
November 27, 1941, hold any conference specifically directed to the
meaning of the messages received from the War and Navy Departments or
concerning action required to be taken pursuant to those messages.
10 JAPANESE ATTACK UPON PEARL HARBOR
For some time prior to November 27, 1941, the War Department and the
Navy Department had under consideration the possibility of sending Army
airplanes to Wake and Midway and withdrawing Marine planes then on those
islands; of relieving marines stationed there by the substitution of
units of the Army. General Short, Admiral Kimmel, and Rear Admiral Bloch
had been in conference concerning this proposal.
At the time of the receipt of the messages of November 27 by Admiral
Kimmel and General Short, respectively, this proposal was a subject of
discussion. General Short held discussions with Admiral Kimmel on
November 27, December 1, 2, and 3 concerning this matter in an effort to
compose certain differences of view. At one of these conferences Admiral
Kimmel inquired of his war-plans officer, Captain McMorris, who was
present, concerning the probability of a surprise air attack on Oahu.
According to General Short, Captain McMorris replied there was no
probability of such an attack; and, according to Captain McMorris, his
reply was that the Japanese would never so attack. According to the
testimony Admiral Kimmel and General Short did not discuss means or
measures for Hawaiian defense to be adopted in the light of the
messages.
On and after November 27, 1941, the commanding general, Hawaiian
Department, and the commander in chief of the Pacific Fleet,
independently took such action as each deemed appropriate to the
existing situation. Neither informed the other specifically of the
action he was taking, and neither inquired of the other whether or not
any action had been taken, nor did they consult as to the
appropriateness of the actions taken by them respectively.
After receipt of the messages of November 27 the following action was
taken:
The commanding general, Hawaiian Department, ordered alert No. 1 (see
next succeeding paragraph) into effect on November 27, and it was
maintained in effect until December 7. At the same time he ordered that
the aircraft warning system operate daily from 4 to 7 a. m. The
commandant of the Fourteenth Naval District, in his capacity as base-
defense officer, called a conference of all the destroyer commanders of
the inshore patrol, advised them that something might happen, and that
they should be on the alert. The commander in chief of the fleet made
certain dispositions of units of the fleet for the purpose of
strengthening his outposts to the south and west of the Hawaiian
Islands, and also issued an order that any Japanese submarines found in
the operating areas around the island of Oahu should be attacked. This
order went beyond the authority given him by the Navy Department.
In the Hawaiian Department's standing operating procedure governing the
defense of the Hawaiian coastal frontier, three states of readiness were
prescribed, known as alert No. 1, alert No. 2, and alert No. 3. Alert
No. 1 was thus defined:
"This alert is a defense against acts of sabotage and uprisings within
the islands, with no threat from without."
Alert No. 2 was thus defined:
"This alert is applicable to a condition more serious than alert No. 1.
Security against attacks from hostile subsurface, surface, and aircraft,
in addition to defense against acts of sabotage and uprisings is
provided."
JAPANESE ATTACK UPON PEARL HARBOR 11
Alert No. 3 was thus defined:
"This alert requires occupation of alt field positions by all units,
prepared for maximum defense of Oahu and the Army installations on
outlying islands."
XIII
The responsibilities of the Army included the installation and operation
of an aircraft warning system for the detection of water-borne and air-
borne craft at a distance from the coast. Throughout the spring and
summer of 1941 the Army was engaged in the installation of permanent
facilities for this purpose on the Hawaiian Islands. Permanent
installations had not, on December 7, 1941, been completed. By November
27, 1941, certain mobile equipment had been installed at temporary
locations, and was being operated intermittently throughout the day for
the purpose of training personnel in its operation. On November 27,
1941, in connection with the order for alert No. 1, the commanding
general, Hawaiian Department, ordered that this system be operated each
day during the period from 4 until 7 a. m. It was intended that in the
near future the Navy should have officer personnel in the information
center, but up December 7 such officers had not been designated. In
accordance with the order in effect, the system closed at 7 a. m.
Sunday, December 7. A noncommissioned officer who had been receiving
training requested that he be allowed to remain at one of the stations,
and as granted leave so to do. At about 7:02 a. m. he discovered what he
thought was a large flight of planes slightly east of north of Oahu, at
a distance of about 130 miles. He reported this fact at 7:20 a. m. to a
lieutenant of the Army who was at the central information center, having
been detailed there to familiarize himself with the operation of the
system. This inexperienced lieutenant, having information that certain
United States planes might be in the vicinity at the time, assumed that
the planes in question were friendly planes, and took no action with
respect to them. The recording of the observation made indicated that
these airplanes were tracked toward the land and then lost.
On November 27, 1941, there was sufficient partially trained personnel
available to operate the aircraft warning system throughout 24 hours of
the day, as installed in its temporary locations. An arc of nearly 360
around Oahu could have been covered.
Admiral Kimmel, on and prior to December 7,1941, assumed that the
aircraft warning system was being fully operated by the Army, but made
no inquiry after reading any of the messages of October and November
from the War and Navy Departments as to what the fact was with respect
to its operation.
XIV
The joint coastal frontier defense plan provided that, when it became
effective, the Army should conduct an inshore airplane patrol, covering
the circumference of the island of Oahu to a distance of about 20 miles.
Prior to December 7, 1941, no inshore patrol was conducted, except
during drills and maneuvers. Pilots were being trained on weekdays, and
the training involved flying around the confines of Oahu from about 8
o'clock in the morning throughout
12 JAPANESE ATTACK UPON PEARL HARBOR
the day. On Sunday morning no inshore airplane patrol conducted.
XV
Under the joint coastal frontier defense plan, when the plan became
effective the Navy was to conduct distinct air reconnaissance radiating
from Oahu to a distance of from 700 to 800 miles. Prior to December
7,1941, no distant reconnaissances were conducted, except during drills
and maneuvers. The fleet from time to time had task forces operating in
various areas off the island of Oahu and, in connection with such
operations, carrier and patrol planes conducted reconnaissances of the
operating areas. The sectors searched, however, constituted but small
arcs of the total arc of 360 , and rarely extended to a radius of 700
miles.
Means were available for distant reconnaissance which would have
afforded a measure of security against a surprise air attack.
General Short assumed that the Navy was conducting distant
reconnaissance, but after seeing the warning messages of October and
November from the War and Navy Departments he made no inquiry with
respect to the distant reconnaissance, if any, being conducted by the
Navy.
XVI
There were, prior to December 7, 1941, Japanese spies on the island of
Oahu. Some were Japanese consular agents and others were persons having
no open relations with the Japanese foreign service. These spies
collected and, through various channels transmitted, information to the
Japanese Empire respecting the military and naval establishments and
dispositions on the island.
In Hawaii the local Army Intelligence Service has always devoted itself
to matters pertaining to Army personnel and property; and the local
Naval Intelligence Service to matters pertaining to Navy personnel and
property. In addition, prior to the establishment of an office of the
Federal Bureau of Investigation in Hawaii, Naval Intelligence
investigated enemy activities amongst the civil population. Then the
Bureau's office was established it was agreed by the three governmental
agencies that the Bureau should take over and become primarily
responsible for investigation of matters connected with the civil
population, and that the three services should cooperate with each
other. Efforts were made by the Bureau to uncover espionage activities
in Hawaii. The United States being at peace with Japan, restrictions
imposed prevented resort to certain methods of obtaining the content of
messages transmitted by telephone or radio telegraph over the commercial
lines operating between Oahu and Japan. The Bureau and the local
intelligence staffs were unable prior to December 7, to obtain and make
available significant information respecting Japanese plans and fleet
movements in the direction of Hawaii.
In the summer of 1941 there were more than 200 consular agents acting
under the Japanese consul, who was stationed in Honolulu, T. H. The
naval district intelligence office raised a question with the Federal
Bureau of Investigation, and with the intelligence officer of the
Hawaiian Department of the Army, whether these agents
JAPANESE ATTACK UPON PEAL HARBOR 13
should not be arrested for failing to register as agents of a foreign
principal as required by statutes of the United States. In conferences
respecting this question, the commanding general, Hawaiian Department
objected to the arrest of any such persons at least until then had been
given notice and an opportunity to register, asserting that their arrest
would tend to thwart the efforts which the Army had made to create
friendly sentiment toward the United States on the part of Japanese
aliens resident in Hawaii and American citizens of Japanese descent
resident in Hawaii and create unnecessary bad feeling. No action was
taken against the agents.
It was believed that the center of Japanese espionage in Hawaii was the
Japanese consulate at Honolulu. It has been discovered that the Japanese
consul sent to and received from Tokyo in his own and other names many
messages on commercial radio circuits. This activity greatly increased
toward December 7, 1941. The contents of these messages, if it could
have been learned, might have furnished valuable information. In view of
the peaceful relations with Japan, and the consequent restrictions on
the activities of the investigating agencies, they were unable prior to
December 7 to obtain and examine messages transmitted through commercial
channels by the Japanese consul, or by persons acting for him.
It is now apparent that through their intelligence service the Japanese
had complete information. They evidently knew that no task force of the
United States Navy was anywhere in the sector northeast, north, and
northwest of the Hawaiian Islands. They evidently knew that no distant
airplane reconnaissance was maintained in any sector. They evidently
knew that up to December 6 no inshore airplane patrol was being
maintained around the periphery of Oahu. They knew, from maps which they
had obtained, the exact location of vital air fields, hangars, and other
structures. They also knew accurately where certain important naval
vessels would be berthed. Their flyers had the most detailed maps,
courses, and bearings, so that each could attack a given vessel or
field. Each seems to have been given in a specified mission.
XVII
The passes and liberty granted the personnel of the Army and Navy in
Hawaii on Saturday, December 6, were normal for a period when the forces
were not upon a war footing, with the following exceptions: The normal
Army guard had been increased by approximately 100 percent; two
battalions of infantry were held in reserve for anti-sabotage defense;
antiaircraft gun crews were maintained on ships in harbor for instant
defense; all Navy personnel, with the exception of those authorized to
be absent, were required to be in their quarters at midnight; all places
of amusement in Honolulu and all entertainments at the Army posts were
closed at midnight; all saloons and drinking places in Honolulu were
closed at midnight.
On the night of December 6 numerous officers of the Army and Navy
attended social functions at various points on the island of Oahu,
principally the usual Saturday functions at the various posts and naval
establishments. The commanding general, Hawaiian Department, and the
commander in chief of the Pacific Fleet were both guests at dinners away
from their posts of command on that evening, but returned to their
quarters at an early hour.
14 JAPANESE ATTACK UPON PEARL HARBOR
The percentages of strength in the Army present for duty on the island
of Oahu at 8 a. m. December 7, 1941, reported by all major echelons and
posts, were: Twenty-fourth Infantry Division, 90 per cent; Twenty-fifth
Infantry Division, 85.6 percent; Coast Artillery Corps, 87.5 percent;
Air Force, 88.9 percent; miscellaneous, including department
headquarters, ordnance, quartermaster, and medical, 92 percent.
Estimated general percentage, 88.8 percent. Reports from large ships and
destroyers that were in Pearl Harbor during the attack show 60 percent
of officers on board and 96 percent of the men. Of 75 vessels of the
fleet, of all kinds, 49 commanding officers were aboard during the
attack and 22 were en route to their ships, 1 was on another ship, and 1
was on authorized leave, which leaves 2 for whom we are unable to
account.
Intoxicating liquor is sold on the island of Oahu, and men on pass or on
liberty have the opportunity to buy and consume it. Following the
established procedure, at home and abroad, the Army exercises
disciplinary control of men on pass through its military police, and the
Navy of men on liberty by the use of shore patrols. These organizations
take into custody any person showing evidence of intoxication. On the
night of December 7, 1941, from 6 p. m. to 6 a. m., arrests of soldiers
by the military police, for intoxication, were 38, and arrests of
sailors by the Navy shore patrol, for intoxication, were 4. By
comparison the arrests of civilians for drunkenness on that night were
39. Thorough inquiry disclosed there is no evidence of excessive
drinking by any officer of either service on that night. The evidence
shows that as respects the use of intoxicating liquor and intoxication,
the conditions amongst the men of the Army and of the Navy on the night
of December 6 compare closely with similar conditions for the several
preceding months. On Saturday, December 6, 1941, the usual percentage of
enlisted strength entitled to passes or liberty took advantage of such
privilege to spend the afternoon or evening in the city of Honolulu.
Application of this ratio to total numbers of all the services then on
the island of Oahu and in Pearl Harbor, amounting to about 75,000 men
indicates that no less than 11,000 soldiers, sailors, and marines
visited Honolulu that afternoon and evening.
In normal times more enlisted men of both services are absent from duty
by permission on Saturday nights than on other nights; and on Saturday
nights more officers are customarily absent than on weekday nights.
On the morning of Sunday, December 7, Army posts and naval vessels and
stations were adequately manned, for the readiness and alert then in
effect, by men fit for duty.
XVIII
The attack on the morning of December 7,1941, was a combined air-raid
and submarine attack on the island of Oahu, a bombardment of Midway, and
a continuous air attack and bombardment on Wake Island.
Available information indicates that the force attacking Oahu consisted
of either three or four Japanese carriers, with supporting surface craft
and a few small submarines, and that this force had maintained radio
silence during its approach, which, except for the submarines, was from
the northward of Oahu.
JAPANESE ATTACK UPON PEARL HARBOR 15
In the attack on Oahu a suspicions object was sighted in the prohibited
area off Pearl Harbor at 6:30 a. m., by the U. S. S. Antares. Between
6:33 and 6:45 this object, which was a small submarine, was attacked and
sunk by the concerted action of a naval patrol plane and the U. S. S.
Ward. A report of this action by the Ward reached the naval-base watch
officer at 7:12 a. m., who notified his chief of staff. The ready
destroyer was despatched to investigate, but no alert warnings were
issued based upon this report. Another small submarine was fired upon,
depth-charged, rammed, and sunk inside the harbor between 8:35 and 8:43
a. m. A third small submarine grounded in Kaneohe Bay and was captured.
There is no evidence of any damage by torpedoes fired by these
submarines.
Pearl Harbor was provided with an anti-torpedo net which would have
prevented the entrance of torpedoes into the harbor, and would have
revealed the entrance of a submarine. The procedure prior to December 7,
1941, was to keep the net closed during the hours of darkness, opening
it only when necessary for a vessel to pass through. It was kept open
during daylight hours, on the theory that, during daylight the channel
entrance destroyer, the net vessel, and other vessels in the vicinity,
would detect a submerged or partially submerged submarine. December 7
the net was opened at 4:58 a. m. for the entrance of two mine sweepers.
It was kept open until 8:40 a. m., when it was closed by orders. The net
was not damaged. The submarine was first sighted in the harbor at 7:45
a. m. The time of its entrance is not known, but probably it passed in
about 7 a. m.
An estimated force of from 150 to 200 fighting, bombing, and torpedo
planes simultaneously attacked Pearl Harbor and all air bases Oahu at
about 7:55 a. m. All attacking planes had withdrawn before 11 a. m. As a
result of the attack serious loss of life was caused and serious damage
was inflicted on ships in the harbor, and planes, hangars, and other
facilities at Hickam Field, Ewa Field, Ford Island, Wheeler Field,
Bellows Field, and Kaneohe.
The major part of the damage to ships in Pearl Harbor resulted from
torpedoes launched from planes. The torpedoes were of an obsolete type,
altered to increase their explosive load, to decrease their radius, and
fitted with side vanes to insure functioning in shallow water a weapon
peculiarly adapted to an attack such as the one delivered upon ships in
Pearl Harbor. Many of the bombs had extra heavy cases, and appeared to
be modified armor-piercing shell.
December 7, 1941, at 9:30 p. m. Midway time (11: 30 p. m. Honolulu
time), a force believed to consist of two cruisers and two destroyers,
approaching from the southward, opened fire and shelled Midway Island
for about 30 minutes. About noon December 8, 1941 (2:50 p. m. December
7, Honolulu time), some 27 land planes made strafing and bombing attack
on Wake Island. Some loss of life and damage to material resulted on
each island. Attacks on Wake continued until its capture on December 22,
1941 (December 21, Honolulu time).
Immediately upon realizing that the Japanese were attacking, the
commanding general, Hawaiian Department, ordered alert No. 3. The alert
was executed with reasonable promptness. At the same time the commander
in chief placed the fleet on a full war basis and
16 JAPANESE ATTACK UPON PEARL HARBOR
issued a series of orders in an effort to intercept and destroy the
attacking force.
Officers and enlisted men, in defending against the attack, demonstrated
excellent training and high morale. Antiaircraft weapons aboard ship,
which were not already manned, and antiaircraft weapons ashore, which
were in position, were promptly manned. Junior officers and enlisted men
on their own initiative procured from storage every possible automatic
weapon. These weapons continued in action during and in spite of low-
level strafing and dive bombing which have been known to demoralize even
seasoned troops. At least three fighter pilots, in total disregard of
their own safety, attempted to take off in the face of greatly superior
forces then attacking their airdrome, but lost their lives in the
attempt. A few fighter planes parked on an outlying gunnery training
field, which was not attacked, took the air. This combined antiaircraft
and fighter action resulted in the destruction of approximately 30 enemy
aircraft, and a number of others were lost at sea because they were
unable to rejoin their carriers.
XIX
The state of readiness prescribed for Army aircraft prior to the attack
required them to be ready for flight only after 4 hours' notice. The
type of alert in effect required all Army aircraft to be concentrated in
order more effectively to guard against possible sabotage instead of
being dispersed in order to afford greater security against air attack,
and greater facility in taking the air. This state of readiness, this
concentration of airplanes, and the element of surprise, all contributed
to the effectiveness of the Japanese attack, and resulted in such
permanent or temporary disablement of airplanes that very few fighter
airplanes were able to take the air during the course of the action. For
the same reasons it was impossible to get airplanes into the air in time
to trail the Japanese airplanes back to their carriers.
The aircraft warning system, which was remanned by about 8:30 a. m.
December 7, 1941, failed during the balance of that day to furnish any
reliable information of enemy aircraft returning to their carriers. Such
information as it afforded indicated enemy forces to the southward and
southwestward of Oahu. A report of an actual contact with an enemy
carrier, which later proved to be erroneous, gave credence to numerous
reports from other sources indicating enemy carriers might be to the
southward and southwestward thus causing futile searches in those areas.
On December 7 Naval Task Force 8 was about 200 miles west of Oahu,
proceeding toward Oahu. Another was about 700 miles west of Oahu. A
third, Task Force 11, was in the vicinity of Johnston Island, about 700
miles southwest of Oahu. These task forces were engaged in operations
connected with strengthening the defenses of the outlying islands.
On the morning of December 7, 1941, prior to the attack, the following
searches of sea areas were being made. Six patrol planes were searching
south and southeastwardly from Midway. These patrol planes were in the
air engaged in a joint exercise with submarines south of Oahu. Eighteen
scouting planes from Task Force 8 had been dispatched to scout in
advance of the force which was on its way to
JAPANESE ATTACK UPON PEARL HARBOR 17
Oahu. These scouted to the southwestward of Oahu. After the attack
following searches were made: The 3 planes in the air south of Oahu,
according to their standing orders, searched to the northwest of Oahu a
distance of about 375 miles. Nine planes were dispatched by Task Force 8
and searched to the south and southwest of Oahu. Carrier planes of Task
Force 11 searched in an area about 500 miles southwestward of Oahu.
About 11:27 a. m. 2 heavy Army bombers and 4 light bombers took off to
attack a carrier reported about 25 miles off Barber's Point. After
failure to make contact the 2 heavy bombers searched first to the
southwestward and then in areas to the northwest of Oahu. The other 4
searched to the southwestward. At 11:50 a. m. 6 Navy VS planes searched
southward of Oahu. Thereafter 9 planes searched the sector southwest to
northwest of Oahu. Two utility planes searched northward of Oahu to a
distance of 300 miles, and 9 planes which had arrived from carriers and
refueled searched some 200 miles to the northward. No contacts were made
with enemy aircraft or carriers, except that 1 Navy airplane was
attacked by a Japanese airplane some 300 miles north of Oahu. This
incident was not reported until the next day.
SUMMARY OF THE MORE IMPORTANT FACTS
Pearl Harbor is an important outlying naval base, and its security is
vital to both offensive and defensive operations. It is the Army's
function to insure the security of Pearl Harbor against hostile attack,
and the Navy's function to support the Army indirectly by operations at
sea and directly by making available therefor such instrumentalities of
the Navy as are on the vessels of the fleet when in harbor and are
located or based on shore either temporarily or permanently.
Effective utilization of the military power of the Nation is essential
to success in war and requires that the operations of the Army and the
Navy be coordinated. Under the then existing plans the joint defense of
the Hawaiian frontier was to be coordinated by mutual cooperation
between the commanders concerned. Plans for the defense of the Hawaiian
coastal frontier were prepared by the commanding general, Hawaiian
Department, and the commandant of the Fourteenth Naval District, the
latter acting as a subordinate of the commander in chief of the Pacific
fleet. Adherence to such a plan prepared in advance of hostilities does
not suffice to relieve commanders of their responsibility to apply and
adapt the plan to the situation as it develops.
Where, as here, the defense of an area is the joint responsibility of
two commanders who are to coordinate their activities by mutual
cooperation, the first duty of such commanders in the case of an
emergency is conference and consultation with respect to the measures to
be taken under the existing plans and the adaptation of those plans in
whole or in part to the situation.
At about the time that Admiral Kimmel and General Short assumed their
respective commands, the War and Navy Departments were in correspondence
with respect to adequate defense against air raids on Oahu and the naval
base. The correspondence between the departments exhibits a deep concern
respecting the probability of this form of attack. These commanders were
acquainted with this
18 JAPANESE ATTACK UPON PEARL HARBOR
correspondence. Nevertheless there has been amongst the responsible
commanders and their subordinates, without exception, a conviction,
which persisted up to December 7, 1941, that Japan had no intention of
making any such raid. Consequently this form of attack was a complete
surprise to all of the superior officers of Army and Navy stationed in
the Hawaiian area. This conviction persisted notwithstanding messages
containing warnings and orders, brought to the attention of both
commanders over a period of weeks prior to the attack. As early as
October 16 the commanders were warned of the possibility of an attack by
Japan on the United States and were directed to take precautions and
make preparatory dispositions in the light of this information. A
significant warning message was communicated to both the local
commanders on November 24. On November 27 each responsible commander was
warned that hostilities were momentarily possible. The warnings
indicated war, and war only.
Both of these messages contained orders. The commanding general was
ordered to undertake such reconnaissance and other measures as he deemed
necessary. The commander in chief of the fleet was ordered to execute a
defensive deployment in preparation for carrying out war tasks. Other
significant messages followed on succeeding days. These emphasized the
impending danger and the need for war readiness.
In this situation, during a period of 10 days preceding the Japanese
attack, the responsible commanders held no conference directed to a
discussion of the meaning of the warnings and orders sent them. And
failed to collaborate and to coordinate defensive measures which should
be taken pursuant to the orders received. Dispositions as a result of
the messages were independently made by each commander. Neither of them
informed himself of the measures and dispositions taken by the other.
The dispositions so made were inadequate to meet a surprise air attack.
Both commanders were handicapped by lack of information as to Japanese
dispositions and intent. The lack of such knowledge rendered more urgent
the initiation of a state of readiness for defense.
The personnel, materiel, and equipment were insufficient to place the
forces on a war footing and maintain them on that footing for an
extended period. These deficiencies did not preclude measures which
would have to a great extent frustrated the attack or mitigated its
severity.
A considerable number of the Army and Navy personnel were on pass or
liberty December 6, for the reason that the state of alert or of
readiness demanded by the emergency had not been put into effect. With
immaterial exceptions Army and Navy personnel had returned from leave
and liberty hours before the attack ensued, fit for duty.
Both officers and men responded immediately in the emergency and
exhibited initiative, efficiency, and bravery in meeting the raid.
Based upon its findings of fact, the Commission reaches the following
JAPANESE ATTACK UPON PEARL HARBOR 19
CONCLUSIONS
1. Effective utilization of the military power of the Nation is
essential to success in war and requires: First, the coordination of the
foreign and military policies of the Nation; and, second, the
coordination of the operations of the Army and Navy.
2. The Secretary of State fulfilled his obligations by keeping the War
and Navy Departments in close touch with the international situation and
fully advising them respecting the course and probable termination of
negotiations with Japan.
3. The Secretary of War and the Secretary of the Navy fulfilled their
obligations by conferring frequently with the Secretary of State and
with each other and by keeping the Chief of Staff and the Chief of Naval
Operations informed of the course of the negotiations with Japan and the
significant implications thereof.
4. The Chief of Staff and the Chief of Naval Operations fulfilled their
obligations by consulting and cooperating with each other, and with
their superiors, respecting the joint defense of the Hawaiian coastal
frontier; and each knew of, and concurred in, the warnings and orders
sent by the other to the responsible commanders with respect to such
defense.
5 The Chief of Staff of the Army fulfilled his command responsibility by
issuing a direct order in connection with his warning of probable
hostilities, in the following words: "Prior to hostile Japanese action
you are directed to undertake such reconnaissance and other measures as
you deem necessary."
6. The Chief of Naval Operations fulfilled his command responsibility by
issuing a warning and by giving a direct order to the commander in
chief, Pacific Fleet, in the following words:
This despatch is to be considered a war warning.
And
Execute an appropriate defensive deployment preparatory to carrying out
the tasks assigned.
7. The responsible commanders in the Hawaiian area, in fulfillment of
their obligation so to do, prepared plans which, if adapted to and used
for the existing emergency, would have been adequate.
8. In the circumstances the responsibility of these commanders was to
confer upon the question of putting into effect and adapting their joint
defense plans.
9. These commanders failed to confer with respect to the warnings and
orders issued on and after November 27, and to adapt and use existing
plans to meet the emergency.
10. The order for alert No. 1 of the Army command in Hawaii was not
adequate to meet the emergency envisaged in the warning messages.
11. The state of readiness of the naval forces on the morning of
December 7 was not such as was required to meet the emergency envisaged
in the warning messages.
12. Had orders issued by the Chief of Staff and the Chief of Naval
Operations November 27, 1941, been complied with, the aircraft warning
system of the Army should have been operating: the distant
reconnaissance of the Navy, and the inshore air patrol of the Army,
20 JAPANESE ATTACK UPON PEARL HARBOR
should have been maintained; the antiaircraft batteries of the Army and
similar shore batteries of the Navy, as well as additional antiaircraft
artillery located on vessels of the fleet in Pearl Harbor, should have
been manned and supplied with ammunition: and a high state of readiness
of aircraft should have been in effect. None of these conditions was in
fact inaugurated or maintained for the reason that the responsible
commanders failed to consult and cooperate as to necessary action based
upon the warnings and to adopt measures enjoined by the orders given
them by the chiefs of the Army and Navy commands in Washington.
13. There were deficiencies in personnel, weapons, equipment, and
facilities to maintain all the defenses on a war footing for extended
periods of time. But these deficiencies should not have affected the
decision of the responsible commanders as to the state of readiness to
be prescribed.
14. The warning message of December 7, intended to reach both commanders
in the field at about 7 a. m. Hawaiian time, December 7, 1941, was but
an added precaution, in view of the warnings and orders previously
issued. If the message had reached its destination at the time intended,
it would still have been too late to be of substantial use. In view of
the fact that the commanders had failed to take measures and make
dispositions prior to the time of its anticipated receipt which would
have been effective to warn of [ward off?] the attack or to meet it.
15. The failure of the officers in the War Department to observe that
General Short, neither in his reply of November 27 to the Chief of
Staff's message of that date, nor otherwise, had reported the measures
taken by him, and the transmission of two messages concerned chiefly
with sabotage which warned him not to resort to illegal methods against
sabotage or espionage, and not to take measures which would alarm the
civil population, and the failure to reply to his message of November 29
outlining in full all the actions he had taken against sabotage only,
and referring to nothing else, tended to lead General Short to believe
that what he had done met the requirements of the warnings and orders
received by him.
16. The failure of the commanding general, Hawaiian Department, and the
commander in chief, Pacific Fleet, to confer and cooperate with respect
to the meaning of the warnings received and the measures necessary to
comply with the orders given them under date of November 27, 1941,
resulted largely from a sense of security due to the opinion prevalent
in diplomatic, military, and naval circles, and in the public press,
that any immediate attack by Japan would be in the Far East. The
existence of such a view, however prevalent, did not relieve the
commanders of the responsibility for the security of the Pacific Fleet
and our most important outpost.
17. In the light of the warnings and directions to take appropriate
action, transmitted to both commanders between November 27 and December
7, and the obligation under the system of coordination then in effect
for joint cooperative action on their part, it was a dereliction of duty
on the part of each of them not to consult and confer with the other
respecting the meaning and intent of the warnings, and the appropriate
measures of defense required by the imminence of hostilities. The
attitude of each, that he was not required to inform him-
JAPANESE ATTACK UPON PEARL HARBOR 21
self of, and his lack of interest in, the measures undertaken by the
other to carry out the responsibility assigned to such other under the
provisions of the plans then in effect, demonstrated on the part of each
a lack of appreciation of the responsibilities vested in them and
inherent in their positions as commander in chief, Pacific Fleet, and
commanding general, Hawaiian Department.
18. The Japanese attack was a complete surprise to the commanders and
they failed to make suitable dispositions to meet such an attack. Each
failed properly to evaluate the seriousness of the situation. These
errors of judgment were the effective causes for the success of the
attack.
19. Causes contributory to the success of the Japanese attack were:
Disregard of international law and custom relating to declaration of war
by the Japanese and the adherence by the United States to such laws and
customs.
Restrictions which prevented effective counter-espionage.
Emphasis in the warning messages on the probability of aggressive
Japanese action in the Ear East, and on anti-sabotage measures.
Failure of the War Department to reply to the message relating to the
anti-sabotage measures instituted by the commanding general, Hawaiian
Department.
Non-receipt by the interested parties, prior to the attack, of the
warning message of December 7, 1941.
20. When the attack developed on the morning of December 7, 1941, the
officers and enlisted men of both services were present in sufficient
number and were in fit condition to perform any duty. Except for a
negligible number, the use of intoxicating liquor on the preceding
evening did not affect their efficiency.
21. Subordinate commanders executed their superiors' orders without
question. They were not responsible for the state of readiness
prescribed.
Respectfully submitted.
OWEN J. ROBERTS.
W. H. STANDLEY.
J. M. REEVES.
FRANK R. MCCOY.
JOSEPH T. MCNARNEY.
[January 23, 1942]